title: Fluorescence Turn on Sensor for Sulfate Ion in Aqueous Medium Using Tripodal-Cu(2+) Ensemble.
abstract: We report the selective recognition of sulfate anion in aqueous medium at biological pH 7.2 over the other interfering anions based on naphthoic acid bearing tripodal ligand by applying fluorescence turn off -on mechanism. The carboxylic acid groups in the ligand enhance the solubility in water and enable it to form complex with copper salt. Thus formed L-Cu2+ ensemble quench the fluorescence of the parent ligand and in turn recognize sulfate anion via revival of fluorescence intensity. The 1:2 stoichiometry was confirmed by ESI mass spectral data and Job's plot. The average binding constant was found to be 6.2×10(8) M(-2).
authors.affiliation: Department of Chemistry, Indian Institute of Technology Guwahati, Assam, 781 039, India.
authors.forename: Md Najbul
authors.initials: MN
authors.lastname: Hoque
authors.affiliation: Department of Chemistry, Indian Institute of Technology Guwahati, Assam, 781 039, India.
authors.forename: Arghya
authors.initials: A
authors.lastname: Basu
authors.affiliation: Department of Chemistry, Indian Institute of Technology Guwahati, Assam, 781 039, India. gdas@iitg.ernet.in.
authors.forename: Gopal
authors.initials: G
authors.lastname: Das
mesh_terms: D003300:Copper / Q000737:chemistry*; D005453:Fluorescence; D057230:Limit of Detection; D013431:Sulfates / Q000032:analysis*; D014465:Ultrasonics; D014867:Water / Q000737:chemistry*
chemical_list: D013431:Sulfates; D014867:Water; D003300:Copper
keywords: Aqueous medium; Fluorescence turn off-on sensor; Naphthoic acid based tripodal; Sulfate sensing